KVM: Use u64 for frame data types

For 32bit machines where the physical address width is
larger than the virtual address width the frame number types
in KVM may overflow. Fix this by changing them to u64.

[sfr: fix build on 32-bit ppc]

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>